i have done alot of printing and i just can't grasp the contrast increase and decrease with this enlarger I can't understand the channels please help

-- kerrie bray (crazikerrie@yahoo.com), August 20, 2001

Answers

More yellow you decrease contrast, more magenta you increase contrast! Is this a problem related to your enlarger? if so open the chamber and see if the dichoric filters are going into the light path as you increase or decrease your filter amount. if this is a RGB controler then more blue increases contrast, more green decreases contrast. If this this not help then maybe you should explain in more detail what the problem is.

-- Jorge Gasteazoro (jorgegm@worldnet.att.net), August 20, 2001.

Kerrie: Whichever brand of variable contrast paper you are using should have included a guide for the amount of filtration needed to effect a one grade change in contrast. The amount of filteration to either soften or increase contrast can be fairly large. For instance, my set up using Forte VC FB calls for 25Y for printing the equivalent of a #2 print while a #4 print would require 80M. Make a series of test prints starting with no filtration, then add filteration in about 20 unit stages. Do this with both yellow and magenta. you should readily see differences.

-- Arden Howell (serenisea@aol.com), August 22, 2001.

Never use the colour head (magenta, yellow) to decrease or increase contrast. Use the filterset from Ilford with the gradations 00 to 5 and then, you will become the contrast you wanted. Put the filters under the lens. A colour enlarger and his magenta or yellow is not made to print black and white. It is the worsed thing that can happen.

-- Patrick Pevenage (pepeasinus@pi.be), September 02, 2001.

Just trying to make sure that I understand the last reply. Are you really saying that you should not use the filters built into colour heads to get the filtration required to vary the contrast on VC paper? I've never heard of that before... Many people seem to do it with no problem.

-- Ed Hurst (BullMoo@hotmail.com), September 05, 2001.